Kook . . . plumbing? Horsebarn? do you stable the leapin lipozard horses that use toilets? Must be some septic system to handle all those solids! Real horses poop on the ground!
Seon, so your saying a single beam, supported on ends, 20 feet long, with distributed load of 2x6's on 24" centers with 3/4 T&G waferboard on top. What load do you want to carry on top of the deck? 80 lbs/sqare foot? more? less?
